compiler    := gcc
extra_flags :=
use_neon    := 0
release	    := release
DYLIB	    := so
PREFIX      := /usr
INSTALLDIR  := $(PREFIX)/lib/retroarch/filters/video

ifeq ($(platform),)
   platform = unix
   ifeq ($(shell uname -s),)
      platform = win
   else ifneq ($(findstring Darwin,$(shell uname -s)),)
      platform = osx
      arch     = intel
      ifeq ($(shell uname -p),powerpc)
         arch = ppc
      endif
   else ifneq ($(findstring MINGW,$(shell uname -s)),)
      platform = win
   endif
endif

ifeq ($(platform),gcc)
extra_rules_gcc := $(shell $(compiler) -dumpmachine)
endif

ifneq (,$(findstring armv7,$(extra_rules_gcc)))
extra_flags += -mcpu=cortex-a9 -mtune=cortex-a9 -mfpu=neon
use_neon := 1
endif

ifneq (,$(findstring hardfloat,$(extra_rules_gcc)))
extra_flags += -mfloat-abi=hard
endif

ifeq (release,$(build))
extra_flags += -O2
endif

ifeq (debug,$(build))
extra_flags += -O0 -g
endif

ldflags := $(LDFLAGS) -shared -Wl,--version-script=link.T

ifeq ($(platform), unix)
DYLIB = so
else ifeq ($(platform), osx)
compiler := $(CC)
DYLIB = dylib
ldflags := -dynamiclib
   ARCHFLAGS=
   MINVERFLAGS=
   ifeq ($(shell uname -p),arm)
      MINVERFLAGS = -mmacosx-version-min=10.15 -stdlib=libc++ # macOS  (Metal, ARM 64bit)
   else ifeq ($(HAVE_METAL),1)
      MINVERFLAGS = -mmacosx-version-min=10.13 -stdlib=libc++  # macOS  (Metal, x86 64bit)
   else ifeq ($(shell uname -p),powerpc)
      MINVERFLAGS = -mmacosx-version-min=10.5  # macOSX (PowerPC 32-bit)
   else ifeq ($(shell uname -m),i386)
      MINVERFLAGS = -mmacosx-version-min=10.6  # macOSX (OpenGL, x86 32bit)
   else
      MINVERFLAGS = -mmacosx-version-min=10.7 -stdlib=libc++ # macOSX (OpenGL, x86 64bit)
   endif

	# Build for a specific architecture when ARCH is defined as a switch
   ifeq ($(ARCH),arm64)
      MINVERFLAGS  = -mmacosx-version-min=10.15 -stdlib=libc++ # macOS  (Metal, ARM 64bit)
      ARCHFLAGS    = -arch arm64
   else ifeq ($(ARCH),x86_64)
      ifeq ($(HAVE_METAL),1)
         MINVERFLAGS  = -mmacosx-version-min=10.13 -stdlib=libc++
      else
         MINVERFLAGS  = -mmacosx-version-min=10.7  -stdlib=libc++
      endif
      ARCHFLAGS       = -arch x86_64
   else ifeq ($(ARCH),x86)
      MINVERFLAGS     = -mmacosx-version-min=10.6
      ARCHFLAGS       = -arch x86
   else ifeq ($(ARCH),ppc)
      MINVERFLAGS     = -mmacosx-version-min=10.5
      ARCHFLAGS       = -arch ppc
   endif
   ifeq ($(BUILDBOT),1)
      ARCHFLAGS       = -target $(LIBRETRO_APPLE_PLATFORM) -isysroot $(LIBRETRO_APPLE_ISYSROOT)
   endif
	extraflags += $(MINVERFLAGS) $(ARCHFLAGS)
	ldflags += $(MINVERFLAGS) $(ARCHFLAGS)
else
extra_flags += -static-libgcc -static-libstdc++
DYLIB = dll
endif

CC      := $(compiler)
CXX     := $(subst CC,++,$(compiler))
flags   := $(CPPFLAGS) $(CFLAGS) -fPIC $(extra_flags) -I../../libretro-common/include
asflags := $(ASFLAGS) -fPIC  $(extra_flags)
objects :=
flags   += -std=c99

ifeq (1,$(use_neon))
ASMFLAGS := -INEON/asm
asflags += -mfpu=neon
endif

objects += blargg_ntsc_snes.$(DYLIB) \
			  phosphor2x.$(DYLIB) \
			  epx.$(DYLIB) \
			  lq2x.$(DYLIB) \
			  2xsai.$(DYLIB) \
			  super2xsai.$(DYLIB) \
			  supereagle.$(DYLIB) \
			  2xbr.$(DYLIB) \
			  darken.$(DYLIB) \
			  scale2x.$(DYLIB) \
			  normal2x.$(DYLIB) \
			  normal2x_width.$(DYLIB) \
			  normal2x_height.$(DYLIB) \
			  normal4x.$(DYLIB) \
			  scanline2x.$(DYLIB) \
			  grid2x.$(DYLIB) \
			  grid3x.$(DYLIB) \
			  gameboy3x.$(DYLIB) \
			  gameboy4x.$(DYLIB) \
			  dot_matrix_3x.$(DYLIB) \
			  dot_matrix_4x.$(DYLIB) \
			  upscale_1_5x.$(DYLIB) \
			  upscale_256x_320x240.$(DYLIB) \
			  picoscale_256x_320x240.$(DYLIB) \
			  upscale_240x160_320x240.$(DYLIB)

all: build;

%.o: %.S
	$(CC) -c -o $@ $(asflags)  $(ASMFLAGS)  $<

%.o: %.c
	$(CC) -c -o $@ $(flags) $<

%.$(DYLIB): %.o
	$(CC) -o $@ $(ldflags) $(flags) $^

build: $(objects)

clean:
	rm -f *.o
	rm -f *.$(DYLIB)

strip:
	strip -s *.$(DYLIB)

install:
	mkdir -p $(DESTDIR)$(INSTALLDIR)
	cp -t $(DESTDIR)$(INSTALLDIR) $(objects) *.filt

test-install:
	DESTDIR=/tmp/build $(MAKE) install
